Fermented foods are a hot topic in the area of gut and overall health. If you have IBS, you may be wondering whether they might help your gut and you should include them in your diet. And, you may be wondering how they can fit into a low FODMAP diet. Let’s explore all these important questions!
What Are Fermented Foods
Fermented foods are made when yeast and/or bacteria ferment the carbohydrate portion of food to produce alcohol (as in wine or beer) or an acid (as in yogurt or sourdough bread). The process brings about changes in the taste and texture of the food that we have come to love. It has been around for thousands of years as a way to preserve foods before the era of refrigeration. Today, commonly consumed fermented foods and beverages include yogurt, kefir, kombucha tea, tempeh, miso, kimchi, and fermented cheeses.
As beautifully illustrated in this infographic from the International Scientific Association for Probiotics and Prebiotics (ISAPP), some of these foods still contain live bacteria (yogurt, kefir, fresh kimchi, sauerkraut). But others don’t, as the live cultures are killed by further processing. This happens, for example, through baking (as in sourdough bread) or pasteurization (as in wine, beer, and others).
The Benefits of Fermented Foods
Whether they are a source of live bacteria or not, these foods have several benefits. They have better digestibility, and increased availability of certain vitamins/minerals and other important compounds. In addition, they have reduced levels of anti-nutrients (such as phytates). Most of the health benefits of eating fermented foods have been seen in epidemiological studies. In this type of study, we can only observe an association between a behavior and a health outcome. The benefits observed include reduced mortality and improved blood sugar control.
However, there have been also a few controlled studies (the type of study that can show a cause and effect) suggesting positive effects on blood pressure and total cholesterol. Interestingly, new clinical research is also showing how they can benefit gut health. Nonetheless, it is difficult to say whether people with chronic conditions, such as IBS, would benefit from regular consumption of these foods. We need more research in this area!
Fermented Foods and FODMAPs
If you are currently following a low FODMAP diet, you need to know that fermentation can either increase or decrease the FODMAP content of foods. But you can certainly include some fermented foods into your diet. Here is a list of low or high-FODMAP fermented foods at standard serving sizes. Check the Monash FODMAP App for more detailed and up-to-date information.
Low in FODMAPs
- Sourdough bread
- Lactose-free yogurt and kefir
- Tempeh
- Miso
- Some fermented cheese
- Kimchi
High in FODMAPs
- Regular yogurt and kefir
- Kombucha
- Sauerkraut
Bottom line
Fermented foods have documented health benefits, although we still don’t know much about how they may affect people with IBS. If you are trying to find relief from gut symptoms with a low FODMAP diet, you may want to prefer the low FODMAP options. After you have reintroduced the high FODMAP groups and have figured out which ones trigger your symptoms, you may be able to expand the variety of fermented foods you can have.
Still struggling with IBS symptoms such as bloating, gas, and unpredictable bathroom habits?
